1. FIELD OF THE INVENTION
This invention relates to the stabilization of diagnostic reagents which are used to detect the presence or absence of a biological condition, usually in blood, serum, plasma, urine, saliva, such as pregnancy, syphillis, rheumatoid factor, infectious mononucleosis, serum sickness, Forssman antibodies, and Beta steptococcal infections.
2. DESCRIPTION OF THE PRIOR ART
Prior diagnostic compositions in general use in this field are normally liquid wherein antibodies, antigens, or hormones are bound onto an inert tag latex, isotope, dye, magnetic bead, etc., so that when the biological substance is mixed with the diagnostic composition, a network is formed and clumps, color change, detectable signal, etc., result to indicate the presence or absence of the condition. These devices must either be freeze dried, causing loss in yield and difficulty to process, or maintained in a frozen or refrigerated condition, which is inconvenient to distribute, transport, and store.
A device is described in U.S. Pat. Nos. 4,578,282 and 4,493,821, which contain similar specifications and are divisionals, both to Harrison, wherein a precoated, "dry" slide is provided. A fixative composition for a proteinaceous substance which is reactive in a diagnostic immunological reaction is provided, comprised of certain pecentages of pyrrolid-2-one (referred to herein as 2-pyrrolidinone), polyol, urea, and zinc salt. There are certain disadvantages to the Harrison device which the present invention improves upon. Price, U.S. Pat. Nos. 3,666,421 and 3,770,383 also show diagnostic test slides which contain dried immunochemical reagent which upon being moistened with body fluid to be tested forms a spot of reaction mixture. In each case in the prior art, the stabilizing composition is insufficient for the purposes of the present invention.